Concrete-mixer.



PATENTED MAY 19, 1908.

G. J. STAPPORD.

CONCRETE MIXER.

APPLICATION FILED AUG.13,1907.

GEORGE J. STAFFORD, OF MCGRAW, NEW YORK.

CON GEE TE M1XER.

I No. 888,199.

To all whom it may concern:

Be it known that I, GEORGE J. STAFFORD, a citizen of theUnited States, and resident of McGraw, in the county of Cortland, in the State of New York, have invented new and useful Improvements in Concrete-Mixers, of which the following, taken in connection with the accompanying drawings, is a full,

'tion;

clear, and exact description.

.This invention pertains to machines which are designed more particularly for mixing concrete, and it relates to the class of machines comprising a set of blades or paddles consisting of metal bars mounted on a revoluble shaft and arranged in pairs within a cylindrical drum into which the materials are introduced to be subjected to the action of the said blades, the blades of each pair being disposed radially in relation to the shaft and extending in opposite directions therefrom. c

The present invention resides in the construction of the mixing-blades and in the manner of attaching the same to the shaft, one object being to provide a mixing-inachine of the aforesaid character with blades arranged in pairs which can be easily and conveniently, and at the same time independently, detached from the shaft and replaced thereon when required for repairs or the renewal of parts.

Another object of the present invention is to provide the outer or free ends of the blades with means adapted to be adjusted so as to cause the ends to travel at the required distance from the inner periphery of the cylindrical drum, and whereby the blades may be extended to take up wear on the said ends.

To that end the invention consists in the novel arrangement and combination of parts hereinafter fully described and set forth in the claims.

In the accompanying drawings Figure 1 is a sectional view of a portion of a mixing-machine illustrating a pair of blades constructed and su portedin accordance with my invenig. 2 is a plan view; and Fig. 3 is a transverse section on the line XX in Fig. .1.

Referring to the drawings 1 represents a stationary cylindrical drum which is commonly used in concrete-mixing machines, and 2 denotes the usual revoluble shaft extending axially through the drum, which parts may be supported in various ways. (Not necessary to be shown.) This shaft is Specification of Letters Patent.

Application filed August 13, 1907. Serial No. 388,410.

Patented May 19, 1908.

formed angular in cross-section, preferabl square, and may be dr1ven by any sultab mechanism.

denote the mixin -blades each formed preferably from a met bar whic'his rectangular in cross-section or consistin of a casting of any suitable metal. Said ades are arranged in pairs, those of each pair extending radially and in opposite directions from the'shaft 2 and rigidly secured thereto by means of a clip wh1ch comprises two members formedintegral with the respective blades.

The clip-members are produced by primarily providing the inner end portions of the blades with corresponding right-angled off' sets 44- forming shoulders abutting against two opposite faces .55. of the square shaft 2, and secondarily deflecting the blades at right angles to the off-sets to form straps 6-6- lying across the other two faces --77 of the shaft, the

strap of each blade extending beyond the shaft so as to lap onto the main portion of the other blade.

The lapping portions of the two blades are provided with coinciding apertures 88 through which are inserted bolts 99 which firmly clamp the parts to the shaft as Each of said blades clearly shown in F1g. 1. is preferably provided intermediateits ends with a quarter-twist which tends to stiffen the same, andwhereby the blade is caused to present an edge to the concrete materials uring the operation of mixing.

On the free end of each blade is mounted a late 10 which is adapted to be adjusted ongitudinally thereon so asto permit the plate to be set in proper position in relation to the inner periphery of the drum 1 incident to wear on the plate, and it also serves as an extension whereby the blade may be made to accommodate drums of different diameters. These plates also effectually as sist in the operation of mixing the concrete or other materials. To effect this adjust ment, I preferably form the plate with a rectangular groove 1 1 receiving the blade, and provide the grooved portion with an aperture 12 coinciding with a longitudinal slot -13- provided in the blade, through which aperture and slot passes a bolt 14 serving to clamp the platein its position. I

In machines of this type, each pair of mixcured'tonthdshaft by means of a key or setserew, and in order to remove a pair of blades, it is necessary to siide the same ofi the'end of the shaft. This requires the removal ofother blades and consun'ies a great deai of time and labor and is veryvincom vement.

it will be ap arent in the present construe tion, that eaci pair of blades canhe inde-w pendentiy, and at the same time quickly and easily, detached from and attached to the shaft, thus nermitting repairsor renewal of parts to be readily madewhen required What 1 claim as m invention 18;;- In a machine of t e character specified,

the eombination with a cylindrical drum, a

revoiuble shaft extending axially there through, and a setof Uniting-blades fastened at one end to the shaft and arran ed in separaole airs extending substantia y radially from t e shaft, said blades consisting of thin metal bars formed rectangularin cross-section and each bar provided with a quarter twist intermediate of its endsto resent an edge to the concrete-materials, an the outer end portion provided with a longitudinal slot, of a set of weareplates mounted on the free ends of the blades, eachplate having a groove of rectangular form in cross-section to receive the blade and pIOflddvmth an a erture coinciding with the slot 111 the b ade, and each plate having its outer edfie curved in conformity with the inner perip ery of the drum, and clamcfingbolts passing through the said slots an apertures for Se curing the plates adjustably inrelation to the periphery of the drum as and for the pur I pose'set forth.

' GEORGE J.STAFFORD; [i.s] .Witnesses: v

GEORGE W. SWIFT, D. B. TRIIEP. 

